Method of launching aircraft



15, 1932- w. v. N. POWELSON ET AL 1,837,860

METHOD OF LAUNCHING AIRCRAFT Original Filed Sept. 6, 1921 DEIDDUEIEIUEIEIUEI 177216771075 Niifrzid 11H. 7 021162602? Warren Travcrii by -Kw Q il'ariieys Patented Nov. 15, 1932 WILFRID V. N. POWELSON,

PATENT" omen? OF New YORK, are, AND WARREN r'nav'nnn. or sex" nammnnmo, CALIFORNIA;

METHOD LAUNGHING- AIRCRAFT original application filed September 6, 1921, Serial No. 498,605. Divided and this applicatioaflled March 17, 1931. Serial No. 523,247.

This invention pertains to a novel method of launching aircraft.

More particularly it provides for the safe and eflicient lifting of aircraft from ground for the starting of a flight. It relates particularly to cases where the aircraft can sustain itself whenonc'e safely started, but for any ofvarious reasons has difliculty in starting, which may be due to its own condition or to its surroundings. It involves, in one embodiment of the invention, the use of a tractor airship, and is herein illustratedas such. It may be applied for'sta-rting the flight of a ship of" lighter than air type which is laden too heavily to be raised by the buoyancy of its own lifting gas. v

In current practice, airships set upon their flight from mooring inasts or from the ground. The ship is first inflated with lifting gas to such an extent that it is statlcally light; i. e., lighter than the air at the earths surface] Upon being released its inherent buoyancy causes it to ascend under the influence of its own lifting gas; and this ascent will be'vertical, except as effected by local air currents, or by its own propellers.

For the reason that, as altitude is gained the atmosphere around the ship is found at lesspressure, there is increased bursting pressure within the gas containers. Unless special measures are taken the pressure increases to such anextent that safety requires the wasting of good lifting gas to the atmosphere. The higher the selected cruising level of the airship, the greater is this waste of gas,

a factor which limits the recognized desirability of cruising at high elevations to m1n1- mize air-resistance.

By the present invention, the usual waste- 4o ful discharge of uncontaminated lifting gas into the atmosphere is obviated. This is done by elevating the ship by external means while it is still statically heavy, so that when as a whole is, assumed to be adequately equipped to sustainitself when once it has been this raised and started in flight.

Inth-e accompanying drawing, forming a part hereof, there is represented more or: less diagrammatically an arrangement which, serves to lift the airship from the ground to cruising levels in accordance with the teach ings of the invention. y In the drawing, therejis shown attached to the airship 41 an auxiliary aircraft or tractor ship 4 tobe used in the lifting of the airship 41 when-such airship is loaded so aslto be heavier than the air displaced thereby. This tractor shlp l may be equipped with helicopters l0 driven byleng ines 11 for increasing its lifting power or itmay derive the excess-liftingv power which is required from lighterthan-air gas whichmaly beof an inferior quality not adapted for long continned use in the cruising airship and which after serving its purpose of lifting the excess weight of said airship may be wasted from containers 21 and 22 into the atmosphere.

Another economical method for accomplishing this same object is provided for in this invention, and consists in the heating of the gases contained within the tractorship 4 to, provide this required extra buoyancy, or these several methods may be vcombined to produce the required result.

After thus lifting the heavier-than-air cr'uiserAl and attaining such speed that the aerofoils 12,1?) of the cruiser 41 will there, after provide the requisite liftingpower', the connections 5 and 6 between the two vessels are cast loose and the tractor ship returns to its station, while the cruiser proceeds on its way. V

In cases where .aerofoils are arranged at the top of the ship and the propellers44 are Wholly at the bottom, it may be found that the drag'of 'theaerofoils introduces too great a turning moment If this be so',-orif it be desired for otherv reasons, one or more propellers s'et onlongitudinal axes may be arranged at the level of the aerofoils. These (not shown) may either'be driven from" ad? jace'nt engines-like the propellers 44 and the helicopters 101or by power transmitted from 100 engines below by mechanism of well known yp By this simple means, wastage of valuable lifting gas from the airship 41 is avoided. In

operation, the-tractor airship is attached to the statically heavy airship tlas shown in the drawing and the necessaiyliftthereby supplied. As altitude is gained, the density of the atmosphere decreases, with the result that the gas in airship 41 gradually expands while beingstill retained oncboard, and for was insuflicient to sustain the cruising ship,

becomessufiicient; and when the descent is made for landing at the end of voyage the buoyancy of ship is adequate to permit of the reduction of speed with consequent cessation of lift by aerofoils.

It will be understood that other aircraft, including airplanes, as well as airships, may be launched as herein described. c l The situation in which the invention is par- 7 ticularly useful as applied to airplanes arises in the case of heavily laden planes, as those about to undertake a transocea'nic flight, which cannot readily get up sufiicient ground speed for the craft to be lifted into the air on its planes; also in cases where any plane has insufficient runway to surmount the obstacles in the'desired take-off course.

In either case, airship or airplane, the

*7 craft avoids ground obstacles by'being lifted more or less vertically by the applied buoyancy of the tractor ship. Being well up, it can acquire speed while thus safely suspended, both by propulsion of its own engines and by forward traction from. the speedy tractor ship; or, in absence of the latter traction, at least by having its own independent propulsion unhampered either by ground resistance, or by retardation due to its having to tow the buoyant body that is supplying the lift. With the high speed thus obtainable by an indefinitely long starting run, high in air, it can acquire a measure of dynamic lift from its oWn plane. With the speed thus attained while attached it may acquire astate of independent dynamic sustentation suflicient for its normal protracted flight; but if the speed of the tractor ship be no enough for that, the lifted ship will at least have attained a speed approaching will The sub'ect matter of this application has been divided out of our copending application Serial No. 498,605, filed September 6, 1921, for airships. It is intended that the patent to be based on the present application shall cover, by suitable expression in the appended claims, whatever features of patentable novelty reside in the particular invention herein disclosed.

We claim:

1. Apparatus for launching an airship of lighter than-air type comprising means attachable to and detachable from said airship for lifting and supporting it while getr ting under way, while loaded so that the airship and its load are heavier than the air which they displace.

2. Apparatus for operating an airship supported by lighter-than-air gas, comprising propelling engines; auxiliary means attachable to and detachable from said airship for lifting and supporting it while getting under way, while loaded so that the airship and its load are heavier than the air which they displace; and lifting planes attached to the airship for supporting the excess load during flight.

3. Apparatus for handling freight carried by an airship containing lighter-than-air gas, comprising auxiliary aircraft having a lifting power sufficiently in excess of that required for its own support in the air to carry the excess weight of freight in an airship laden so that its gross weight is greater than the Weight of ,the air which it displaces; means for connecting the said auxiliary aircraft to the airship for launching the airship in its flight and subsequently detaching it; and lifting planes attached to the airship for supporting during flight the excess load carried by the airship. fllhe combination of a cruising airship containing a lighter-than-air gas the total weight of which, including the movable weights on board, exceeds the upward lifting force of the lighter-than-air gas; a tractor airship containing a gas lighter for equal volume, than the surrounding atmosphere, the total weight of which tractor airship, including the movable Weights on board, is less than the upward lifting force of, the lighter-than-air gas on board thereof; and means for attaching the tractor airship to and detaching the tractor airship from the cruising airship; where by the combined liftingforce of the lifting gases of both airships may be made to lift into the air the combined weight of both airships, including the movable weights on board, and whereby upon reaching the desired altitude the cruising airship may be released from the tractor airship. i

5. The combination of a cruisin airship containing on board a quantity 0 lighterthan-air gas in containers; a separate container containing a gas lighter for equal volume than the surrounding atmosphere; and means to attach to and detach from the cruising airship said separate container; whereby the net lifting force of the said separate container may be applied to lift the cruising airship to the desired altitude above the ground and whereby the cruising airships may be released from said separate container at said altitude.

6. The combination of a cruising airship containing on board a quantity of lighterthan-air gas in containers; a separate container containing a gas at a temperature above that of the surrounding atmosphere and lighter for equal volume than the surrounding atmosphere; and means to attach said separate container to and detach said separate container from said cruising airship; whereby the net lifting forceof said separate container may be applied to lift the cruising airship to the desired altitude above the ground and whereby the cruising'airship may be released from said separate container at said altitude.

7. In equipment for airships containing lighter-than-air gas, the combination with an airship, which with its load is heavier than the air displaced thereby, of an auxiliary aircraft for launching said airship at the start of a flight. v

8. The combination of a cruising airship containing a lighter-than-air gas, the total weight of which airship, including the movable weights on board, exceeds the upward lifting force of the lighter-than-air gas; a

. separate tractor airship containing a gas lighter for equal volume than the surrounding atmosphere; and means to attach the tractor to and detach the tractor from the cruising airship; whereby the combined lifting force of the lifting gases of both airships may be made to lift into the air the combined weight of both airships, including the movable weights on board, and whereby upon reaching the desired altitude the cruising air ship may be released from the tractor.

from ground level a statically heavy aircraft of carrier type, comprising the combination wlth said carrier aircraft of an aircraft of tractor type, detachably attached in lifting relation to the carrier, said tractor having means for exerting on the carrier a predominantly upward characteristic; the two said craft severally having forwardpull of propulsion power plants of a capacity to drive the two craft severally; forward at equal speed, while attached together, each said craft being thus driven independently of its connection to the other, and the said speed being sufficient for the heavy craft to maintain itself in air upon being detached.

11. A launching unit for the putting into flight of a self-propelling aircraft which has means to maintain itself up, when in air, but which is statically so heavy that its own weight hinders its'rising from the ground,

comprising the combination of a main craft, which is the said heavy aircraft; and an auxiliary aircraft, which is an air-buoyant tractor aircraft having means for exerting on the heavy craft a pull of predominantly'upward characteristic, and is equipped with power means for its own forward propulsion, detachably attached to the heavy aircraft; said statically heavy main craft being of a type including its own said forward-propulsive force and an externally derived vertically acting force of air-buoyancy, said combined forces being applied simultaneously and temporarily during the elevating of the craft from ground level and its propulsion into independent self sustaining flight.

13. The art of launching into independent flight an aircraftwhich has means to maintain itself in air, as by lifting planes, when driven by its own forwardpropulsive force, but is statically so heavy that its weight hinders its rising from the ground; comprising the applying of diverse forces to said craft, including its own said forward-propulsive force and an externally derived force of pre dominantly vertical characteristic, said com bined forces being applied simultaneously and temporarily during the elevating of'the craftfrom ground level and its propulsion into independent self sustaining flight.

Signed at San Bernardino, California, this eleventh day of November, 1930.

WILFRID V. N. POWELSON. WARREN TRAVELL. 

